Electric arc furnaces are used to melt different metallurgical elements such as iron coming from scrap, iron ore, etc. The metal is melted by intense heat created by an electrical arc produced between an electrode and the scrap or ore. The electric arc furnace is basically composed of a shell to retain the scrap and melted metal; a set of electrodes to create the arcs needed to melt the metal; a set of actuators, which are controlled by a regulator, to control the electrodes distance from the scrap; and a large current power supply to supply the arc currents. When the melting is completed, impurities that float to the surface are skimmed or scraped from the surface and the liquid metal is poured from the shell for further processing.
The most important aspect of arc-furnace operation is productivity optimization, which includes energy efficiency. Thus, an electric arc-furnace is operated to produce the greatest amount of metal using the least amount of energy possible. The primary source of energy in an electric arc furnace is produced by the utilization of electricity. This electrical energy is complemented by chemical energy. Chemical energy may be derived from but not limited to a chemical reaction, (CO+O=CO2), or by the burning of oxygen or natural gas. A good electric arc furnace operation will balance the total energy input for production, efficiency and cost. Any furnace problems such as electrical arc instability or electrode degradation adversely affect productivity by increasing electricity usage and/or processing time. Monitoring an electric arc furnace to insure that it is operating optimally increases the productivity of the furnace. This monitoring typically involves monitoring an amount of current flowing in an electrode. If the monitored current flow indicates a non-optimal operation, the controlling regulator's operation is then changed based upon the measured value of the electrode current. Unfortunately, simply altering the regulator's performance only compensates for the problem without addressing or identifying the underlying root cause of the problem. Therefore, in view of the above discussed limitations of the prior art, what is needed is an improved method and system for monitoring an arc furnace's performance that increases productivity without requiring substantial increases in labor costs.